Bazinga! Physicists crack ‘Big Bang Theory’ problem

Fusion reactors could help shed light on dark matter

University of Cincinnati

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UC Professor Jure Zupan is a theoretical physicist who studies topics such as dark matter.

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Credit: Joseph Fuqua II

A professor at the University of Cincinnati and his colleagues figured out something two of America’s most famous fictional physicists couldn’t: theoretically how to produce subatomic particles called axions in fusion reactors.

Particle physicists Sheldon Cooper and Leonard Hofstadter, roommates in the CBS sitcom “The Big Bang Theory,” worked on the problem in three episodes of Season 5 but couldn’t crack it.

Now UC physics Professor Jure Zupan and his theoretical physicist co-authors at the Fermi National Laboratory, MIT and Technion–Israel Institute of Technology think they have one solution in a study published in the Journal of High Energy Physics. 

Axions are hypothetical particles that physicists suspect could help explain dark matter. Researchers are interested in dark matter because it helps explain the evolution of the universe after its creation in the Big Bang nearly 14 billion years ago.

Dark matter has never been observed directly, but physicists believe it represents a majority of the mass in the universe that is attributed to matter, while only a fraction is due to normal, visible matter. Dark matter is called dark because unlike normal matter it does not absorb or reflect light.

Nevertheless, physicists have identified its existence through its gravitational effects, modifying motion of galaxies in the universe and stars in the galaxies. One of the main theoretical possibilities for dark matter is that it is a very light particle, the so-called axion. 

In their paper, Zupan and his colleagues considered a fusion reactor powered by deuterium and tritium in a vessel lined by lithium that is being developed in a global collaboration in the south of France. Such a reactor would produce not only energy but potentially also dark sector particles due to a large flux of neutrons that will be created in a fusion reactor.

“Neutrons interact with material in the walls. The resulting nuclear reactions can then create new particles,” he said.

The second way the new particles can get generated is when neutrons bounce off other particles and slow down, releasing energy in a process physicists call bremsstrahlung or “braking radiation.”

The new particles could be axions, or at least axion-like particles. And that’s where the show’s fictional physicists failed, Zupan said.

“The Big Bang Theory” ran from 2007 to 2019 and earned seven Emmys. It remains among the most-watched shows of any streaming service, according to Nielsen.

“The general idea from our paper was discussed in ‘The Big Bang Theory’ years ago, but Sheldon and Leonard couldn’t make it work,” Zupan said.

In one episode, a white board features an equation and diagram that Zupan said describes how axions are generated from the sun. In a subsequent episode, another equation appears on a different board. Below the calculations in a different marker color is an unmistakable sad face — a symbol of failure.

Zupan said Leonard and Sheldon’s equation estimates the likelihood of detecting axions from their proposed fusion reactor compared to the sun — with discouraging results, which explains the sad face.

“The sun is a huge object producing a lot of power. The chance of having new particles produced from the sun that would stream to Earth is larger than having them produced in fusion reactors using the same processes as in the Sun. However, one can still produce them in reactors using a different set of processes,” he said.

The characters in the show never talk about axions or the white boards in the episodes. They’re just an Easter egg for physicists in a show famous for incorporating scientific concepts like Schrodinger’s cat and the Doppler effect into its storylines, along with cameos by Nobel laureates and “Star Trek” alumni alike.

“That’s why it’s fantastic to watch as a scientist,” Zupan said. “There are many layers to the jokes.”

  

University of Cincinnati Profesor Jure Zupan is a theoretical physicist who studies topics such as dark matter.

Credit

Joseph Fuqua II

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Journal

Journal of High Energy Physics

DOI

10.1007/JHEP10(2025)215 

Article Title

Searching for exotic scalars at fusion reactors

 

Making Sense of Schrodinger’s Cat

Review of "The Midnight Library"

by Eric Walberg / May 23rd, 2025

How can a cat be alive and dead at the same time?

I love how science has rediscovered religion. Leaving aside the Big Bang theory of the origin of the universe, the universe itself is conscious. In the beginning was consciousness — inner light. Then there was outer light, etc. Mind you it took billions of years, but what’s that in divine reckoning? Religion was the first ‘science’, followed by astrology. Now both despised. How times have changed.

The scientific method, induction, deduction, math/physics, Darwin are all latecomers, though Darwin marks the beginning of the return to metaphysics. His theory was turned into a mindless, machine-like Nature, to be deconstructed, dissected (gruesomely for billions of guinea pigs), but a careful reading shows he was not so scientistic as the Darwinian Establishment that followed him. He admitted we’ll never understand the peacock. Beauty.

Henri Bergson started from there and developed a more lively ‘creative evolution‘ which was more or less politely ignored by science, though the Nobel committee awarded him the prize for literature in 1927, ‘in recognition of his rich and vitalizing ideas and the brilliant skill with which they have been presented.’ For a conscious being to exist is to change, to mature, i.e. to go on creating oneself endlessly. Realizing that, Bergson asked: Is it the same for existence in general? Nature is the epitome of creative change, leading to a dazzling, even outrageous variety and beauty.

Is beauty the end goal of a divine process that started with pure consciousness? We bemoan species extinction (rightly as we are here as stewards of Nature), but already 99% of species over time have gone extinct, replaced by others, better adapted to the changing environment (at least until humans starting wiping them out like a house on fire).

I’m okay with the idea of antimatter, dark matter, dark energy, quantum theory, being in two places at the same time, time slowing down the faster you go, everyone ‘marching to their own tune’, but I could never get a grip on multiverses, Schrodinger’s cat being alive and dead at the same time. I’d given up until today, finishing The Mindight Library (2020) by Matt Haig.

Who was that? Oh, just someone I knew in another life.

It starts with Nora’s countdown to her decision to commit suicide. Everything she wanted or tried to do seemed to lead to failure and when she backed out of her marriage, was fired and then her cat died (outside in the rain by the road, retrieved and buried by Ash) and when no one answered her texts/ phone – all this in a dank flat in dreary Bedford, she swallowed sleeping pills and passed out. Nora enters a twilight zone, a library run by her high-school librarian Mrs Elm, a soulmate that had seen her through parental death and her own depressive state.

Mrs Elm gives her The Book of Regrets, Nora’s own missed opportunities in life, roads not taken, and Nora begins her adventures, seeking out her one ‘true’ happy, successful life journey, which she can try out, as each missed opportunity represents an alternate universe in what science now insists is a multiverse, though no one really understands what that means.

Haig seems to, and puts meat on Schrodinger’s bones. Nora wants a live where she took better care of Voltaire, her rescue kitty, so it would live longer. Suddenly she’s lying in bed again, awake, calling for Volts, finally finding him under the bed, cold and dead. He’s still dead! Not the life she wants, so she’s spirited back to the library to try again.

Mrs Elm explains that Volts had a weak heart and no doubt knew its time was near, asked to go out and die alone in peace, i.e., it wasn’t her fault. ‘Some regrets,’ the prim librarian tells Nora, ‘are a load of bullshit. The only way to learn that is to live.’ So one regret down, many to go. In another alt-life, Voltaire, aka Schrodinger’s Cat, is still alive, a healthy Siamese.

The novel really just describes Nora’s last minutes before death as an out-of-body event, a fact that is well-documented. There are many instances of people who have experienced a near- or after-death experience (NDE), an alternate reality, where they could choose to stay or return to the ‘real’ world (though that would be painful).

Coppola’s Youth without Youth (1976) is based on Mircea Eliade’s eponymous novel explaining time, consciousness, and the fantastic foundations of reality. Protagonist Dominic manages to live a few alternate realities after lightning gave him a new life. This is also a take on Nietzsche’s eternal recurrence. I like Haig’s variation on this theme because, well, consciousness is enough of a miracle for me.

So the original Voltaire is dead in one universe and alive in another. Nora standing up her fiance turns out to have been a very wise decision, as were all but one of her alt-lives, where she is happily married to Ash, but …

You are the library card

I won’t ruin the plot for you, but I don’t think it’s a spoiler alert to say she felt each time it was like she had joined the movie halfway. And the prison wasn’t the place, but the perspective. The bluebird of happiness is actually you-know-where. Most/all of these alternate lives turned out to be what others thought Nora should do, not her ‘root life’, making her lose any sense of who she was.

I’ve been doing this sort of musing for a few years now, as I get closer to the end. I like the pro-activeness of The Book of Regrets. You work through each of your alternate universes in your mind, fantasizing happier alt-lives, realizing they wouldn’t ‘be me’, that I wouldn’t be who I am if, say, I had become a musician, or sportsman, or teacher. Probably no books written, no extreme travels, near deaths, polyglot/ polymath (even if half-assed).

I don’t know if these alt-lives exist in some multiverse, with angels and djinn from them occasionally making a visit ‘here’, but like much of science, they are useful constructs to help explain the mystery of consciousness, the mind. You don’t exist because of the library; this library exists because of you. This is just your brain translating something significant. I remember the sense of a new beginning after a near-death experience. I wasn’t in a library, but when I recovered, I had my blank library book to write in, and I’m slowly burning up my Book of Regrets. That’s freedom.

In old age, you must learn to travel, have adventures in you mind. You are only limited by your imagination. You don’t need booze or drugs like in your salad days. The real world experience is too much work and so often disappointing. Your time is short, precious.

Suicide comes a poor second. Nora thinks she wants to die, but you don’t go to death. Death comes to you. You are the library card. So long as there are still books on the shelves, you are never trapped. Every book is a possible escape. That’s what NDEs are all about. Coming back from one is like getting the only book left in your library, one with blank pages. Mrs Elm: That’s the beauty, isn’t it? You just never know how it ends.

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Eric Walberg is a journalist who worked in Uzbekistan and is now writing for Al-Ahram Weekly in Cairo. He is the author of From Postmodernism to Postsecularism and Postmodern Imperialism. His most recent book is Islamic Resistance to Imperialism. Read other articles by Eric, or visit Eric's website.

The imaginary part of quantum mechanics really exists!

FACULTY OF PHYSICS UNIVERSITY OF WARSAW

Research News

 

IMAGE: THE PHOTON SOURCE USED TO PRODUCE QUANTUM STATES REQUIRING DESCRIPTION BY COMPLEX NUMBERS. view more 

CREDIT: SOURCE: USTC

For almost a century, physicists have been intrigued by the fundamental question: why are complex numbers so important in quantum mechanics, that is, numbers containing a component with the imaginary number i? Usually, it was assumed that they are only a mathematical trick to facilitate the description of phenomena, and only results expressed in real numbers have a physical meaning. However, a Polish-Chinese-Canadian team of researchers has proved that the imaginary part of quantum mechanics can be observed in action in the real world.

We need to significantly reconstruct our naive ideas about the ability of numbers to describe the physical world. Until now, it seemed that only real numbers were related to measurable physical quantities. However, research conducted by the team of Dr. Alexander Streltsov from the Centre for Quantum Optical Technologies (QOT) at the University of Warsaw with the participation of scientists from the University of Science and Technology of China (USTC) in Hefei and the University of Calgary, found quantum states of entangled photons that cannot be distinguished without resorting to complex numbers. Moreover, the researchers also conducted an experiment confirming the importance of complex numbers for quantum mechanics. Articles describing the theory and measurements have just appeared in the journals Physical Review Letters and Physical Review A.

"In physics, complex numbers were considered to be purely mathematical in nature. It is true that although they play a basic role in quantum mechanics equations, they were treated simply as a tool, something to facilitate calculations for physicists. Now, we have theoretically and experimentally proved that there are quantum states that can only be distinguished when the calculations are performed with the indispensable participation of complex numbers," explains Dr. Streltsov.

Complex numbers are made up of two components, real and imaginary. They have the form a + bi, where the numbers a and b are real. The bi component is responsible for the specific features of complex numbers. The key role here is played by the imaginary number i, i.e. the square root of -1.

There is nothing in the physical world that can be directly related to the number i. If there are 2 or 3 apples on a table, this is natural. When we take one apple away, we can speak of a physical deficiency and describe it with the negative integer -1. We can cut the apple into two or three sections, obtaining the physical equivalents of the rational numbers 1/2 or 1/3. If the table is a perfect square, its diagonal will be the (irrational) square root of 2 multiplied by the length of the side. At the same time, with the best will in the world, it is still impossible to put i apples on the table.

The surprising career of complex numbers in physics is related to the fact that they can be used to describe all sorts of oscillations much more conveniently than with the use of popular trigonometric functions. Calculations are therefore carried out using complex numbers, and then at the end only the real numbers in them are taken into account.

Compared to other physical theories, quantum mechanics is special because it has to describe objects that can behave like particles under some conditions, and like waves in others. The basic equation of this theory, taken as a postulate, is the Schrödinger equation. It describes changes in time of a certain function, called the wave function, which is related to the probability distribution of finding a system in a specific state. However, the imaginary number i openly appears next to the wave function in the Schrödinger equation.

"For decades, there has been a debate as to whether one can create coherent and complete quantum mechanics with real numbers alone. So, we decided to find quantum states that could be distinguished from each other only by using complex numbers. The decisive moment was the experiment where we created these states and physically checked whether they were distinguishable or not," says Dr. Streltsov, whose research was funded by the Foundation for Polish Science.

The experiment verifying the role of complex numbers in quantum mechanics can be presented in the form of a game played by Alice and Bob with the participation of a master conducting the game. Using a device with lasers and crystals, the game master binds two photons into one of two quantum states, absolutely requiring the use of complex numbers to distinguish between them. Then, one photon is sent to Alice and the other to Bob. Each of them measures their photon and then communicates with the other to establish any existing correlations.

"Let's assume Alice and Bob's measurement results can only take on the values of 0 or 1. Alice sees a nonsensical sequence of 0s and 1s, as does Bob. However, if they communicate, they can establish links between the relevant measurements. If the game master sends them a correlated state, when one sees a result of 0, so will the other. If they receive an anti-correlated state, when Alice measures 0, Bob will have 1. By mutual agreement, Alice and Bob could distinguish our states, but only if their quantum nature was fundamentally complex," says Dr. Streltsov.

An approach known as quantum resource theory was used for the theoretical description. The experiment itself with local discrimination between entangled two-photon states was carried out in the laboratory at Hefei using linear optics techniques. The quantum states prepared by the researchers turned out to be distinguishable, which proves that complex numbers are an integral, indelible part of quantum mechanics.

The achievement of the Polish-Chinese-Canadian team of researchers is of fundamental importance, but it is so profound that it may translate into new quantum technologies. In particular, research into the role of complex numbers in quantum mechanics can help to better understand the sources of the efficiency of quantum computers, qualitatively new computing machines capable of solving some problems at speeds unattainable by classical computers.

The Centre for Quantum Optical Technologies at the University of Warsaw (UW) is a unit of the International Research Agendas program implemented by the Foundation for Polish Science from the funds of the Intelligent Development Operational Programme. The seat of the unit is the Centre of New Technologies at the University of Warsaw. The unit conducts research on the use of quantum phenomena such as quantum superposition or entanglement in optical technologies. These phenomena have potential applications in communications, where they can ensure the security of data transmission, in imaging, where they help to improve resolution, and in metrology to increase the accuracy of measurements. The Centre for Quantum Optical Technologies at the University of Warsaw is actively looking for opportunities to cooperate with external entities in order to use the research results in practice.

CAPTION

Photons can be so entangled that within quantum mechanics their states cannot be described without using complex numbers.

CREDIT

Source: QOT/jch

CONTACTS:

Dr. Alexander Streltsov
Centre for Quantum Optical Technologies, University of Warsaw
tel.: +48 22 5543792
email: a.streltsov@cent.uw.edu.pl

SCIENTIFIC PUBLICATIONS:

"Operational Resource Theory of Imaginarity"
K.-D. Wu, T. V. Kondra, S. Rana, C. M. Scandolo, G.-Y. Xiang, Ch.-F. Li, G.-C. Guo, A. Streltsov
Physical Review Letters 126, 090401 (2021)
DOI: 10.1103/PhysRevLett.126.090401

"Resource theory of imaginarity: Quantification and state conversion"
K.-D. Wu, T. V. Kondra, S. Rana, C. M. Scandolo, G.-Y. Xiang, Ch.-F. Li, G.-C. Guo, A. Streltsov
Physical Review A 103, 032401 (2021)
DOI: 10.1103/PhysRevA.103.032401

LINKS:

https://qot.uw.edu.pl/

The website of the Centre for Quantum Optical Technologies, University of Warsaw.

LA REVUE GAUCHE - Left Comment: Godel, Cantor, Wiener and Schrodinger's Cat (plawiuk.blogspot.com)

Read to succeed -- in math; study shows how reading skill shapes more than just reading

University at Buffalo psychologist identifies a connectivity fingerprint suggesting that the brain's reading network is at work across cognitive domains; 'reading affects everything,' he says

UNIVERSITY AT BUFFALO

Research News

 

BUFFALO, N.Y. - A University at Buffalo researcher's recent work on dyslexia has unexpectedly produced a startling discovery which clearly demonstrates how the cooperative areas of the brain responsible for reading skill are also at work during apparently unrelated activities, such as multiplication.

Though the division between literacy and math is commonly reflected in the division between the arts and sciences, the findings suggest that reading, writing and arithmetic, the foundational skills informally identified as the three Rs, might actually overlap in ways not previously imagined, let alone experimentally validated.

"These findings floored me," said Christopher McNorgan, PhD, the paper's author and an assistant professor in UB's Department of Psychology. "They elevate the value and importance of literacy by showing how reading proficiency reaches across domains, guiding how we approach other tasks and solve other problems.

"Reading is everything, and saying so is more than an inspirational slogan. It's now a definitive research conclusion."

And it's a conclusion that was not originally part of McNorgan's design. He planned to exclusively explore if it was possible to identify children with dyslexia on the basis of how the brain was wired for reading.

"It seemed plausible given the work I had recently finished, which identified a biomarker for ADHD," said McNorgan, an expert in neuroimaging and computational modeling.

Like that previous study, a novel deep learning approach that makes multiple simultaneous classifications is at the core of McNorgan's current paper, which appears in the journal Frontiers in Computational Neuroscience.

Deep learning networks are ideal for uncovering conditional, non-linear relationships.

Where linear relationships involve one variable directly influencing another, a non-linear relationship can be slippery because changes in one area do not necessarily proportionally influence another area. But what's challenging for traditional methods is easily handled through deep learning.

McNorgan identified dyslexia with 94% accuracy when he finished with his first data set, consisting of functional connectivity from 14 good readers and 14 poor readers engaged in a language task.

But he needed another data set to determine if his findings could be generalized. So McNorgan chose a math study, which relied on a mental multiplication task, and measured functional connectivity from the fMRI information in that second data set.

Functional connectivity, unlike what the name might imply, is a dynamic description of how the brain is virtually wired from moment to moment. Don't think in terms of the physical wires used in a network, but instead of how those wires are used throughout the day. When you're working, your laptop is sending a document to your printer. Later in the day, your laptop might be streaming a movie to your television. How those wires are used depends on whether you're working or relaxing. Functional connectivity changes according to the immediate task.

The brain dynamically rewires itself according to the task all the time. Imagine reading a list of restaurant specials while standing only a few steps away from the menu board nailed to the wall. The visual cortex is working whenever you're looking at something, but because you're reading, the visual cortex works with, or is wired to, at least for the moment, the auditory cortex.

Pointing to one of the items on the board, you accidentally knock it from the wall. When you reach out to catch it, your brain wiring changes. You're no longer reading, but trying to catch a falling object, and your visual cortex now works with the pre-motor cortex to guide your hand.

Different tasks, different wiring; or, as McNorgan explains, different functional networks.

In the two data sets McNorgan used, participants were engaged in different tasks: language and math. Yet in each case, the connectivity fingerprint was the same, and he was able to identify dyslexia with 94% accuracy whether testing against the reading group or the math group.

It was a whim, he said, to see how well his model distinguished good readers from poor readers - or from participants who weren't reading at all. Seeing the accuracy, and the similarity, changed the direction of the paper McNorgan intended.

Yes, he could identify dyslexia. But it became obvious that the brain's wiring for reading was also present for math.

Different task. Same functional networks.

"The brain should be dynamically wiring itself in a way that's specifically relevant to doing math because of the multiplication problem in the second data set, but there's clear evidence of the dynamic configuration of the reading network showing up in the math task," McNorgan says.

He says it's the sort of finding that strengthens the already strong case for supporting literacy.

"These results show that the way our brain is wired for reading is actually influencing how the brain functions for math," he said. "That says your reading skill is going to affect how you tackle problems in other domains, and helps us better understand children with learning difficulties in both reading and math."

As the line between cognitive domains becomes more blurred, McNorgan wonders what other domains the reading network is actually guiding.

"I've looked at two domains which couldn't be farther afield," he said. "If the brain is showing that its wiring for reading is showing up in mental multiplication, what else might it be contributing toward?"

That's an open question, for now, according to McNorgan.

"What I do know because of this research is that an educational emphasis on reading means much more than improving reading skill," he said. "These findings suggest that learning how to read shapes so much more."

What is Godel's Theorem?

January 25, 1999

Melvin Henriksen--Professor of Mathematics Emeritus at Harvey Mudd College--offers this explanation:

KURT GODEL achieved fame in 1931 with the publication of his Incompleteness Theorem.

Giving a mathematically precise statement of Godel's Incompleteness Theorem would only obscure its important intuitive content from almost anyone who is not a specialist in mathematical logic. So instead, I will rephrase and simplify it in the language of computers.

Imagine that we have access to a very powerful computer called Oracle. As do the computers with which we are familiar, Oracle asks that the user "inputs" instructions that follow precise rules and it supplies the "output" or answer in a way that also follows these rules. The same input will always produce the same output. The input and output are written as integers (or whole numbers) and Oracle performs only the usual operations of addition, subtraction, multiplication and division (when possible). Unlike ordinary computers, there are no concerns regarding efficiency or time. Oracle will carry out properly given instructions no matter how long it takes and it will stop only when they are executed--even if it takes more than a million year

Let's consider a simple example. Remember that a positive integer (let's call it N) that is bigger than 1 is called a prime number if it is not divisible by any positive integer besides 1 and N. How would you ask Oracle to decide if N is prime? Tell it to divide N by every integer between 1 and N-1 and to stop when the division comes out evenly or it reaches N-1. (Actually, you can stop if it reaches the square root of N. If there have been no even divisions of N at that point, then N is prime.)

What Godel's theorem says is that there are properly posed questions involving only the arithmetic of integers that Oracle cannot answer. In other words, there are statements that--although inputted properly--Oracle cannot evaluate to decide if they are true or false. Such assertions are called undecidable, and are very complicated. And if you were to bring one to Dr. Godel, he would explain to you that such assertions will always exist.

Even if you were given an "improved" model of Oracle, call it OracleT, in which a particular undecidable statement, UD, is decreed true, another undecidable statement would be generated to take its place. More puzzling yet, you might also be given another "improved" model of Oracle, call it OracleF, in which UD would be decreed false. Regardless, this model too would generate other undecidable statements, and might yield results that differed from OracleT's, but were equally valid.

Do you find this shocking and close to paradoxical? It was even more shocking to the mathematical world in 1931, when Godel unveiled his incompleteness theorem. Godel did not phrase his result in the language of computers. He worked in a definite logical system and mathematicians hoped that his result depended on the peculiarities of that system. But in the next decade or so, a number of mathematicians--including Stephen C. Kleene, Emil Post, J.B. Rosser and Alan Turing--showed that it did not.

Research on the consequences of this great theorem continues to this day. Anyone with Internet access using a search engine like Alta Vista can find several hundred articles of highly varying quality on Godel's Theorem. Among the best things to read, though, is Godel's Proof by Ernest Nagel and James R. Newman, published in 1958 and released in paperback by New York University Press in 1983.

LA REVUE GAUCHE - Left Comment: Godel, Cantor, Wiener and Schrodinger's Cat 

LA REVUE GAUCHE - Left Comment: Search results for MATH 

Deconstructing Schrödinger's cat

by Springer

Credit: CC0 Public Domain

The paradox of Schrödinger's cat—the feline that is, famously, both alive and dead until its box is opened—is the most widely known example of a recurrent problem in quantum mechanics: its dynamics seem to predict that macroscopic objects (like cats) can, sometimes, exist simultaneously in more than one completely distinct state. Many physicists have tried to solve this paradox over the years, but no approach has been universally accepted. Now, however, theoretical physicist Franck Laloë from Laboratoire Kastler Brossel (ENS-Université PSL) in Paris has proposed a new interpretation that could explain many features of the paradox. He sets out a model of this possible theory in a new paper in EPJ D.

One approach to solving this problem involves adding a small, random extra term to the Schrödinger equation, which allows the quantum state vector to 'collapse,' ensuring that—as is observed in the macroscopic universe—the outcome of each measurement is unique. Laloë's theory combines this interpretation with another from de Broglie and Bohm and relates the origins of the quantum collapse to the universal gravitational field. This approach can be applied equally to all objects, quantum and macroscopic: that is, to cats as much as to atoms.

The idea of linking quantum collapse to gravity has already been proposed by the great English physicist and philosopher Roger Penrose, but he never developed his ideas into a complete theory. Laloë proposes a model that goes in the same direction, agrees with physical observations and may one day prove testable experimentally. It is relatively simple—'naive," even—and introduces only one additional parameter to the standard equation. Laloë is planning to explore more consequences of his model in different situations. Furthermore, he suggests that a theory that combines quantum mechanics with gravitation may have implications in astrophysics.Physicist disentangles 'Schrodinger's cat' debate

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More information: Franck Laloë, A model of quantum collapse induced by gravity, The European Physical Journal D (2020). DOI: 10.1140/epjd/e2019-100434-1

Journal information: European Physical Journal D